The walls of this home, which are constructed with structural insulated panels (SIPs), combine the framing, insulation, and sheathing into one unit, providing faster assembly and a thermally efficient envelope.

Klingenberg’s I-joist solution, after wrapping with rigid foam insulation. Furring strips screwed to the I-joist flanges through the foam provided a vented rain screen and a place to attach the siding.

SIPs are custom-fabricated in a factory and then shipped via truck to the building site. There, panels are typically set in place by a boom truck.

Panels arrive on the job site ready to assemble, allowing faster construction times than are possible with conventional framing.

A bale knife can be used to trim straw bales for windows and doors, or to aesthetically round wall corners.

Applying the protective stucco outer coat. The wire mesh keeps the stucco from breaking away from the wall.

Lengths of rebar help keep bales aligned. These bales are infill walls, with the load-bearing structure already in place.

Door and window framing in a double-stud wall is more complex compared to standard framing.

One approach to double-stud walls: Separated by a gap that will be filled with insulation, aligned studs help minimize thermal bridging.

Another approaches to double-stud walls: Separated by a gap that will be filled with insulation, staggered studs help minimize thermal bridging.

Durisol ICFs, ready to receive concrete.

Larger Rastra ICF panels require heavy equipment to lift.

Like many other wall systems, ICFs rest on continuous poured-concrete footings.

ICFs consist of two outer layers of rigid foam insulation separated by metal or plastic webbing. After reinforcing steel is added, the forms are filled with concrete.

The REMOTE building technique being applied. Note the waterproof barrier under the layers of rigid foam.

Beginner

Not long ago, 2-by-4 walls insulated with R-13 fiberglass were standard in North American homes, even in regions where winter temperatures fall well below freezing. But residential construction has taken tremendous strides forward. Researchers are helping builders understand much more clearly how heat and moisture move through walls, roofs, and floors. Now, there are a variety of options for building more efficient, comfortable, and durable houses. Tougher building codes promoting energy efficiency and a clamor for lower energy costs have helped advance the technologies, too.

This article will explain some wall-building technologies and techniques in a range of high- and low-tech options. These wall systems come with different price tags and require different construction techniques, some more specialized than others. But all of them are aimed at providing better thermal barriers, fewer air leaks, and lower costs for heating and cooling than conventional stick-frame construction.

One caveat: As houses get tighter, whole-house mechanical ventilation gets more important. If you’re planning a super-insulated house with very low air leakage, make room in your budget for a heat recovery ventilator or its equivalent.

Advanced FramingLess Lumber, More Insulation

Advanced framing (aka optimum value engineering) boils down to less wood and more insulation. This method of framing structurally sound houses with less lumber—saving time and materials—grew out of a partnership between the U.S. Department of Housing and Urban Development and the National Association of Home Builders Research Foundation in the 1970s. Walls built with fewer sticks of wood allow more space for insulation and help reduce thermal bridging—the movement of heat through relatively dense framing members.

Advanced framing technique relies on standard building materials and is relatively easy to adopt, yet yields big returns—30% fewer pieces of lumber and 60% more room for insulation compared to conventional 2-by-4 walls on 16-inch centers. Some of advanced framing’s major differences over conventional wood-framed construction:

2-by-6 studs, on 24-inch centers.

Single top plates and in-line or stack framing—joists are located directly over studs, and studs are located directly over each other on adjacent floors.

Eliminating door and window headers without loads and using single headers for load-bearing openings.

Two-stud corners.

Fewer studs around door and window openings.

Raised-heel roof trusses, allowing more insulation where the roof intersects with the walls.

Some builders haven’t liked some elements of advanced framing. Two-stud outside corners made hanging drywall seem problematic, although drywall clips proved an easy fix. Eliminating one of the top plates on the wall also required that studs be 1 1/2 inches longer to maintain the same ceiling height.

There also was a perception that a house framed this way wouldn’t be strong enough. Builders who learned traditional framing techniques could see the value of using 2-by-6 studs (more room for insulation) but might balk at the 24-inch on-center (o.c.) spacing and fall back on 16-inch o.c. framing.

But once convinced to try, builders could see the improvements in building performance and ease of assembly, as well as lower labor and material costs. The Building Science Corp. estimates that advanced framing saves 13% in space-conditioning costs compared to conventional construction.

Comments (3)

I think that SIPS are the way to go. From poured concrete foundation to enclosed roof in one week! That is pretty good, and almost a requirement in the northwest where rain is frequent, and dry construction timing is short and in-frequent.

No discussion of high-performance walls is complete without considering scandinavian building practices. They build stud framed houses just like we do, and achieve very high performance levels using simple techniques that any American builder can follow. No special materials, no special skills, predictable cost and labor time. We've posted detailed information for builders. There is a video series that gives a brief overview:http://www.youtube.com/watch?v=yZ0W...

But its not all about the wall assembly. The framing method is just as important, and in Sweden they have modified the western platform frame for better performance. Much more effective than so called "advanced framing", Swedish Platform Framing fixes the all the weak performance of the platform framing method.http://blog.lamidesign.com/p/swedis...